Improvement in lock-up safety valve



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IMPROVEMENT IN LOCK-UP SAFETY VALVE.

SPECIFICATION.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, CHILION M. FARRAR', of the city of Buii'a'lo, county of Erie, and State of New York, have invented a new and useful improvement in Lock-up Safety Valve, and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, making a part of this specification, in which- Fig. I is a longitudinal section.

Fig. II is a transverse section, and

Fig. III is a transverse section.

The nature of this invention relates,

1st. To arranging and combining compound levers and safety valve of a steam boiler with a suitable locknp box, a movable and adjustable fulcr'um being arranged to act upon both levers, the shorter lever acting directly upon the safety valve and the longer lever having a weight permanently fixed upon its outer end, these parts being all arranged within the lock-up box.

2d, In the application of a hook in connection with the box and weighted end of the longer lever in such manner that the weighted end of the lever may be lifted by means of the hook, and the safety valve thereby relieved, and so arranged that no additional pressure can be brought upon the safety valve by means of the hook.

` 3d. The arrangement below and under the exhaust pipe and within the box of a wide bar or plate, so as to prevent any intermeddling with the levers or safety valve through the exhaust pipe.

Letters of like name and kind refer to like parts in each of the figures.

A represents a lock-up box of suitable form'and proportion, to be connected with a steam generator so that the safety valve and all the mechanism connected therewith may be protected within 'the box.

. B represents the safety valve, which is of ordinary construction and connected' with the steam pipe, C, in acommon manner. This steam pipe is, by its iiange C1, connected to the steam drum or boiler in alcommon manner. The outer end of this pipe is carried into the box and the safety valve is placed on the end of this pipe and within the box.

' D represents a' short lever, which is hinged to the eye block E, as shown at Dl. This lever passes directly over the safety valve and bears upon its central bar as shown at e. p

F represents a longer lever, which is hinged to the eye block G, as shown at f. It stands directly over and parallel with the shorter lever and has upon its outer end a weight H, which is permanently and immovably fixed thereon.

At I is represented a movableand adjustable fulcrum, which is made to slide upon tne lever F and to which itmay be fixed or set at any point/by means of the set screw J.

This fulcrum has a friction roller K which bears upon the short lever D so that any required amount of pressure'or weight may be made to bearupon the safety valve to hold down by means of adjusting and setting this fulcrum, as will be readily seen by reference to the drawings.

L represents a hook having a long handle. The hook catches under the weighted end of the longer lever, and the handle thereof projects upwardly through the top of the box so that it may be grasped by the end and the weighted end of the lever thereby raised a little, and thereby relieve the safety valve, Vif at any timeit should require such relief. But no additional pressure can be brought to bear upon the safety valve to hold it down by means of this hook. It is designed to quickly relieve the safety valve in case of an emergency.

M representsa steam escape pipe leading out of the box. Just below the end of this pipe and within the box is placed a broad bar or plate, N. It may be supported by and drop down from the upper part ofthe box, or it may be supported in any convenient manner, its object being to prevent any entrance through the pipe to effect the levers in their pressure upon the safety valve.

At O is shown an iron strap and staple for the purpose of attaching a lock thereto to lockfup the box. By virtue of recent laws of the- United States for greater security in the use of steam, government oilcials are to determine the steam pressure a boiler may safely carry, and are to graduate and fix-the weight upon the valve, and then lock up the box and seal it, sorthat the weights cannot be disturbed or changed until the proper authority shall cause the box to be unlocked and a change to be made.

My improvement furnishes the means of accomplishing this object.

The combination and arrangement of the several parts brings the improvement into compact form, so that it can be conveniently and advantageously used and accomplish the pui-Rose required.

What claim as my invention and desire to secure by Letters Patent, is-

1st. The arrangement and combination of compound levers D, F, movable and adjustable fulcrum I, fixed weight H and safety valve B within a suitable lock-up box A, for the purposes and substantially as described.

. 2d. The hook L having a long handle projecting upwardly through the box in combination with the lock.-

up box, for the purpose and substantially as set forth. y

3d. The plate N placed under the escape pipe and within the box A, for the purpose and substantially as described.

CHILION M. FARRAR.

Witnesses: o

E. B.` FoRBUsH, B. H. MUEHLE. 

